Power driven winch and hoist mechanism



Aug. 2, 1955 H. w. PETERSON 2,714,434

POWER DRIVEN WINCH AND HOIST MECHANISM Filed 001'.- 28, 1954 CLUTCHSPEED RESPONSIVE if K I $ELF-ENER6IZED SAFETY BRAKE THROTTLE CONTROLfndemio 1r HaroZcZ UJ peieagsaw United States Patent 2,714,434 POWERDRIVEN WINCH AND HOIST MECHANISM Harold William Peterson, Chicago, Ill.Application October 28, 1954, Serial No. 465,225 4 Claims. (Cl.192-.094)

The present invention relates to a power drive and winch mechanism whichis particularly useful on temporary elevators employed on constructionprojects.

Usually the winches used on construction projects remain continuallyexposed to the elements. Operation often proceeds at temperatures belowfreezing. Since the units must be portable, small pull-rope startedgasoline engines usually furnish the power. These are often hard tostart, particularly if the winch mechanism is directly coupled to theengine as is the conventional practice.

In addition, the engine may stall or otherwise fail when the load israised. Such a stall is both time-consuming and often dangerous to theoperator when the load is in the raised position. Safety in conventionalinstallations demands that the load be lowered to a resting point beforean attempt to start the engine is made.

With the foregoing in mind it is the general object of the presentinvention to furnish a power winch unit which affords greater ease andsafety in starting and operation. A related object of the invention isto provide a gasoline engine powered winch mechanism which can be safelystarted when the load is in the raised position.

Still another object of the invention is to provide a winch power drivewhich is adaptable to many existing winch units.

Further objects and advantages of the invention will become apparent asthe following description proceeds, taken in connection with theaccompanying drawings, in which:

Figure 1 is a perspective view of the winch mechanism employed with atemporary construction elevator on a building site.

Fig. 2 is an enlarged perspective view of the engine, drive, and winchemployed in the elevator shown in Fig. 1.

Fig. 3 is a perspective exploded partially diagrammatic view of thedrive coupling between the engine and winch shown in Fig. 2.

The elevator shown in Fig. l is a typical illustration of the type ofelevator in which the present invention finds utility, and the use forwhich such elevators are employed. Referring now to the drawing, theelevator is in the form of a modified A-frame with a ladder track 11 anda support post 12 completing the A-frame. The load platform 14 ridesalong the ladder track 11 guided by suitable rollers.

The hoisting cable 15 is fixed to the upper portion of the load platform14 at the connector 16, and is reaved over a pulley at the apex of theA-frame (not shown). The cable 15 leads downwardly to the winch assemblyWhere it is coiled over the winch cable drum 21. A self-levellingcontrol cable 18 is normally employed with the elevator in order topreselect the height at which the load platform 14 will automaticallystop.

The winch control and drive assembly 20 is illustrated in greater detailin Fig. 2. There it will be seen that the hoisting cable 15 coilsbetween the guide discs 22 of the cable drum 21. A mechanically operatedcontrol brake 24 is located directly coupled to the winch drum asssemblyand actuated by brake control arm 25.

An additional preloaded self energizing brake assembly 26, which may beloaded when the main clutch is engaged (to be described later) may beprovided at the other side of the winch drum. Both of these brakes areself-energizing in the direction of lowering the load. That is, thebrakes tend to set themselves when the load is lowered, whereas when theload is being raised, even if the operator exerts pressure on thecontrol arm 25 actuating the control brake 24, no extensive brakingaction results. On the other hand, even a slight pressure on the controlbrake arm 25 when the load is moving downwardly will call into actionthe self-energizing features of the brake and immediately lock the winchdrum 21 and hold the load platform in position.

The clutch-throttle assembly comprises a clutch control arm 31 which isconnected to the engine throttle cable 32 at its lower end portion by athrottle grip assembly 34. The effect of this two-fold connectionoperates to advance the throttle of the engine thereby increasing itsspeed and power delivery when the clutch arm 31 is moved in order toactuate the winch mechanism to raise the load. The winch clutch 30itself is actuated by the clutch connecting coupling 35 which engagesthe winch clutch at the winch clutch wrist pin 36.

The gasoline engine 38 is a conventional air-cooled single cylinderengine, the construction or details of which are not specificallycontemplated by the invention. The engine is mounted to the same baseframe 39 as the winch and its drive assembly. The engine-winch assemblydrive coupling 40 transmits the power from the engine to the reductiongear housed in the reduction gear housing 37. The motion of the engineis then converted to a low speed shaft which tunnels through the winchdrum as: sembly and couples to the winch through the clutch assembly 30at the opposite side of the winch drum.

It will be appreciated that considerable heavy grease and lubrication isrequired for this gear reduction and winch drive assembly. In winteroperation particularly when the temperature is below freezing thelubricants offer considerable resistance to the drive transmissionuntil, through operation, the grease is warmed and becomes less viscous.Since the engine is hand started by means of a conventional startingpull rope coiled about the starter pulley 33, the engine may becomeextremely diflicult to start when the operator must .necessarily turnover the entire winch drive mechanism along with the motor.

In operating a conventional winch after the engine is started the clutcharm 31 is moved by the operator to engage the clutch and advance thethrottle. Should the engine kill at any stage the self-energized safetybrake 26 will prevent the load from dropping so long as the clutch isengaged. But the engine cannot be started with the clutch engaged.Consequently the clutch and safety brake must both be released. Then thehandbrake 24 must be actuated to prevent the load from falling. Theoperator cannot safely hold the hand brake arm 25 and start the engine,so he must first lower the load to a resting position. This can, anddoes, prove costly when the masons and other construction men are idledby not having their materials at hand.

In order to overcome these operational difficulties the drive assembly40 has been given an automatic control feature through the combinedaction of a cushioned coupling assembly 41 and a speed-controlled clutch45. The speed-controlled clutch 45 may be of the centrifugallyoperatedvariety which contemplates internal radially positioned elements whichengage an outer drum when a certain centrifugal force is built up by thespeed of the rotating shaft 42. Best operation has been found when theclutch is adjusted to engage at 600 R. P. M., although variations inthis setting are contemplated to fall within the spirit of theinvention. The clutch-driven shaft 44 connects, with the clutch couplingassembly 41. Such a coupling serves the twofold function of cushioningthe inertia load and compensating for misalignment of the drive shaft.The coupling assembly contemplates an internal spider 46 flanked by theprongs 48 of the coupling elements 49. The drive shaft 50 then continuesto trans.- mit the power to the reduction gear assembly 3'7.

In operation, when the engine is started, the operator need only pullover the engine itself, the extensive mechanism of a winch drive andclutch being disengaged at the speed, clutch 45. After the engine isstarted the operator is then free to grasp the winch brake control arm25 with one hand and increase the engine speed through manipulating thewinch clutch control arm and throttle control 31, 32,.

After the engine has exhibited sufficient power and is warmed up, thewinch clutch 30 can be fully engaged. The engine clutch 45 willautomatically engage itself as the winch clutch is engaged becausesimultaneously the engine throttle is advanced which increases the speedof the engine and thereby actuates the speed clutch 45 of the engineinto its driving condition.

In order to further implement the winter starting features of the winchdrive proposed, the engine exhaust pipe assembly 51 may be directed atthe gear assembly 37 at the discretion of the operator. In summeroperation, of course, this additional heat would be undesirable andaccordingly means for selectively controlling the exhaust arecontemplated.

If the load platform 14 should be at the working site and the enginekill, the operator can safely restart since neither the winch clutch 30nor the safety brake 26 need be disengaged. After the engine has reachedits speed the winch is again ready for operation.

Although one particular embodiment of the invention has been shown anddescribed in full here, there is no intention to thereby limit theinvention to the details of such embodiment. On the contrary, theintention is to cover all modifications, alternative embodiments, usagesand equivalents of the winch mechanism and drive as fall within thespirit and scope of the invention, specification and appended claims.

I claim as my invention:

1. In a winch mechanism including a gasoline type engine power source, awinch clutch and throttle control, and a self-energizing load brake, thecombination comprising a low speed disengaging clutch coupled to themotor, and a cushioned coupling between the low speed clutch and thewinch clutch drive.

2. In a winch mechanism including a gasoline type engine power source, awinch clutch and throttle control, a self-energizing load brake, and asecond self energizing safety brake engaged with the clutch, thecombination comprising a low speed automatically disengaging clutchcoupled to the motor, and a cushioned coupling between the low speedclutch and the winch clutch drive.

3. In a winch mechanism including a gasoline type engine power sourceand speed reducing gear box, a winch clutch and throttle control, and aself-energizing load brake, the combination comprising a low speeddisengaging clutch coupled to the motor, a cushioned coupling betweenthe low speed clutch and the winch clutch drive, and selective means fordiverting the hot engine exhaust gases toward the gear box.

4. For use with a gasoline engine powered winch, a drive mechanismcomprising, in combination, a self-energizing load brake on the winch, awinch clutch, drive means connecting the winch clutch to the engine, anda low speed disengaging clutch included in such drive means whichpermits hand starting of the engine without actuating any of the Winchmechanism.

References Cited in the file of this patent UNITED STATES PATENTS

